The aim of this project is to examine the involvement of certain ribonucleases in cellular events. The scope of this project has evolved to include protein chemistry, enzymatic activity, overproduction of proteins and the consequences of changes in the level of enzymatic activity within the cell. The basis for most of the experimental approaches is derived from an enzymological perspective. The ability to examine a particular event in great detail from primary amino acid sequence of a protein to the consequences of alteration of the level of enzymatic activity within the cell has given us the opportunity to study both the enzymological and functional roles of these intriguing enzymes. A second area of interest is mutagenesis in E. coli.